SSI 
03 


Fungicides 

State  Eortic mt-aral  Commission 


'A  ' 


'«W  'IVd 


STATE  HORTICULTURAL  COMMISSION 


ELLWOOD  COOPER,  Commissioner 


FUNGI    AND 
FUNGICIDES 


SACRAMENTO 
W.  W.  SHANNON,  SUPT.  STATE  PRINTING 

1905 


CALIFORNIA  STATE,  COMMISSION  OF 
HORTICULTURE. 


ELLWOOD  COOPER Commissioner Santa  Barbara. 

JOHN  ISAAC Secretary... San  Francisco. 

ED.  M.  EHRHORN Deputy Mountain  View. 

E.  K.  CARNES Assistant  Deputy .Riverside. 

O.  E.  BREMNER Second  Assistant Santa  Rosa. 

GERTRUDE  BIRD Stenographer Sacramento. 


OFFICE: 

ROOM  41,  STATE  CAPITOL,  SACBAMENTO. 
BRANCH  OFFICE,  ROOM  11,  FERRY  BUILDING,  SAN  FRANCISCO. 


FUNGI  AND  FUNGICIDL5. 


Growing  plants  are  liable  to  the  attacks  not  only  of  insects, 
but  also  of  parasitic  fungi.  The  peculiar  maladies  known  as 
fungous  diseases  are  produced  by  the  rapid  development  of  the 
parasitic  fungi.  It  is  estimated  that  in  the  United  States  alone 
the  annual  loss  from  these  minute  vegetable  organisms  runs 
into  millions  of  dollars. 

Fungi  belong  to  the  so-called  lower  plants,  among  which  are 
the  toadstool,  mushroom,  molds,  mildews,  rusts,  smuts,  blights, 
etc.  A  fungus  may  attack  only  dead  tissue  or  decaying  matter, 
as  is  the  case  with  mushrooms  or  toadstools,  or  it  may  attack  only 
animal  life,  as  is  seen  in  the  fungus  which  destroys  the  house 
fly  and  the  chinch  bug.  But  the  most  important  class  of  para- 
sitic fungi  with  which  the  fruit-grower  has  to  deal  are  those 
which  attack  the  live  tissue  of  plant  life — those  which  check 
the  growth  of  trees,  attack  and  spot  fruit,  and  even  cause  an 
early  decay  or  a  total  loss  before  the  crop  is  harvested. 

Fungi  are  plants,  much  the  same  as  trees,  grass,  etc.,  the 
only  difference  being  that  they  do  not  have  the  green  coloring 
matter,  or  chlorophyll,  of  the  latter.  The  seeds,  called  spores, 
are  more  simple  and  are  exceedingly  minute  (microscopic). 
They  are  produced  in  numbers  which  appear  almost  incredible 
to  those  not  versed  on  the  subject. 

Fungi  are  divided  into  two  groups:  the  internal  and  the 
external.  The  internal  fungi  send  their  germ  tubes  into  the 
skin  of  the  leaf,  fruit,  branch,  or  root,  and  the  branching 
threads  (mycelium)  develop  entirely  within  the  tissue  of  the 
host  plant.  This  group  includes  some  of  our  worst  species,  such 
as  peach-leaf  curl,  anthracnose,  brown  rot,  shothole  fungus, 
and  all  the  grain  smuts. 

The  external  fungi  are  surf  ace' feeders,  their  mycelium  spread- 
ing over  the  surface  of  the  fruit,  leaf,  or  branch,  as  the  case 
may  be,  and  are  easily  controlled  by  the  use  of  sprays.  To  this 
group  belong  the  powdery  mildews  of  the  apple,  grape,  rose, 
gooseberry,  etc. 

266800 


v  :  FUKGC 


.  FUNGICIDES. 


It  will  be  readily  seen  that  quick  action,  perseverance,  and 
good  judgment  on  the  part  of  the  grower  are  necessary  to 
obtain  satisfactory  results.  Especially  is  this  true  of  the 
internal  fungi,  which  must  be  attacked  before  the  germ-tube 
enters  the  tissue. 

PEACH-LEAF  CURL. 

In  some  seasons  this  fungus  is  very  severe,  and  on  some 
varieties  of  peach  more  than  on  others.  It  can  be  easily 
recognized  by  the  abnormal  growth  of  the  leaf,  which  becomes 
leathery,  highly  colored,  and  sometimes  resembles  a  seed-pod 
more  than  a  leaf. 

In  winter  use  the  lime-sulphur-salt  wash  or  the  Bordeaux 
mixture  (formula  A). 

Just  as  the  buds  are  swelling  use  the  Bordeaux  mixture 
(formula  B). 

APPLE  OR  PEAR  SCAB. 

This  is  one  of  the  most  common  diseases  of  pomaceous  fruits 
the  world  over.  It  does  not  reduce  the  crop,  nor  does  it  seem  to 

affect  the  vitality  of  the 
tree,  but  it  injures  the 
quality  of  the  fruit,  mak- 
ing it  unsalable.  The 
grower  knows  too  well 
that  a  scabby  or  a  de- 
formed pear  has  no  sale 
in  the  market  or  at  the 
cannery,  in  fact  is  only  fit 
for  hog  feed;  therefore, 
the  utmost  vigilance  and 
greatest  care  should  be 
exercised  in  the  applica- 
tion of  remedies  to  check 
this  disease.  The  first 
appearance  of  the  scab  is 
seen  upon  the  new  growth 

and  small  fruit  as  a  velvety  spot.  The  disease  is  easily  recog- 
nized, and  if  not  soon  checked  the  velvety  spots  on  the  fruit 
continue  to  spread  until  they  have  the  appearance  of  black, 
scabby,  corky  blotches.  As  the  pears  grow,  the  development 
of  the  affected  side  is  arrested,  but  the  healthy  side  continues 


FIG.  1.    The  effect  of  the  fungus  on  one-  and 
two-year-old  pear  branches  and  leaves. 


FUNGI   AND   FUNGICIDES.  5 

to  develop  very  fast  and  begins  to  twist  or  double  over  the 
affected  side,  making  a  very  ugly  looking,  misshaped  fruit. 

Spray  with  the  lime-sulphur-salt  wash  as  late  in  winter  as 
possible. 

Spray  with  the  Bordeaux  mixture  (formula  A)  while  the 
buds  are  unfolding.  If  the  season  permits,  a  second  and  third 
spraying,  ten  days  apart,  using  formula  B,  will  prove  beneficial. 


SHOTHOLE  FUNGUS. 

This  disease  has,  of  late,  become  very  prevalent,  attacking 
all  the  stone  fruits,  and  has  been  especially  destructive  to  the 


FIG.  2.    Appearance  of  the  fungus  on  an  apple.  FIG.  3.    A  blotch— enlarged. 

apricot.  It  makes  its  appearance  upon  the  leaves,  forming 
reddish-brown  spots,  which,  when  mature,  shrink  from  the 
surrounding  tissue  and  are  blowrn  away,  leaving  the  leaf 
perforated.  When  the  fungus  attacks  the  fruit,  it  first  appears 
as  minute  red  pimples,  which  are  very  often  mistaken  for  scale 
insects.  These  soon  develop  and  burst  open  at  the  top,  the 
new  spores  escaping  and  spreading  the  disease.  The  old  spot 
forms  a  scab,  which  spreads  and  joins  others,  and  soon  the 
surface  becomes  very  rough,  rendering  the  fruit  unsalable. 

Spray  with  the  lime-sulphur-salt  solution  in  winter,  and  use 
the  Bordeaux  mixture  (formula  B)  just  when  the  buds  are 
swelling.  If  the  lime-sulphur-salt  remedy  is  not  used,  then 
the  Bordeaux  mixture  (formula  A)  should  be  applied  as  early 
in  the  season  as  possible. 


FUNGI    AND    FUNGICIDES. 


BROWN  ROT. 

The  brown  or  fruit  rot  of  stone  fruits  is  known  in  but  few 
localities  in  the  State.  Wherever  this  disease  occurs,  its  pres- 
ence is  shown  by  the  ashy  gray  spores  on  the  surface  of  the 
fruit.  Sometimes,  where  several  fruits  are  clustered  together, 
a  small  brown  spot  appears  and  rapidly  spreads  until  the 
whole  becomes  shrunken,  soft,  and  discolored.  The  interior 


FIG.  5.    Pear  cracking. 


FIG.  6.    Leaf  blight. 


of  fruits  which  do  not  indicate  much  outward  attack  will  show 
a  brownish,  rotten  appearance  when  cut  open. 

Wherever  the  disease  exists,  care  should  be  taken  to  gather 
all  diseased  fruit,  generally  known  as  mummied  fruit,  which 
may  cling  to  the  fruit  spurs  or  fall  to  the  ground,  as  the  spores 
thereon  will  infect  the  next  year's  crop. 

The  same  remedies  as  are  used  for  pear  scab  will  check  this 
disease. 


FUNGI   AND    FUNGICIDES.  7 

POWDERY  MILDEW  OF  APPLE,  PEACH,  AND  OTHER  TREES. 

During  the  summer  months  one  may  notice  the  leaves  and 
new  growth  of  fruit  trees  covered  with  a  thick,  white,  felt-like 
covering.  These  are  the  mycelium  of  the  powdery  mildew 
fungus.  This  fungus  belongs  to  the  external  group,  the 
mycelium  of  which  live  on  the  outside  of  the  plant  and  do  not 
enter  the  tissue  of  the  leaf.  Early  in  the  fall  of  the  year  the 
winter  spores  are  developed  and  consist  of  very  minute,  round, 
black  masses,  which  remain  on  the  fallen  leaves  or  twigs  dur- 
ing the  winter  and  from  which  start  the  next  season's  brood. 

Use  the  ammoniacal  solution  of  copper  carbonate  when  the 
leaves  first  open,  and  in  very  bad  cases  repeat  three  or  four 
times  at  intervals  of  fourteen  days. 

BITTER  ROT  OF  THE  APPLE. 

This  fungus  has  appeared  in  various  apple  districts.  The 
time  to  spray  for  it  is  when  it  first  makes  its  appearance. 
This  disease  can  be  easily  recognized  by  the  presence  of  small 
blackish  pustules  scattered  over  the  surface  of  the  apple. 
These  are  the  fruiting  spots  of  the  fungus.  The  mycelium 
enter  the  pulpy  tissue  of  the  fruit  and  cause  the  rot  to  appear 
in  little  brown  specks  underneath  the  skin. 

In  very  bad  cases  the  first  spraying  should  be  followed  by  a 
second  and  third  spraying  at  intervals  of  two  weeks,  using  the 
ammoniacal  copper  carbonate  solution. 

PRUNE-LEAF  RUST. 

The  leaves  of  the  prune  and  other  stone  fruits  are  often 
attacked  by  reddish  spots  on  the  surface  and  yellowish-brown 
spots  on  the  under  side.  Sometimes  this  attack  is  so  severe 
as  to  cause  the  dropping  of  the  foliage. 

Spraying  with  the  Bordeaux  mixture  (diluted  formula)  just 
after  the  buds  start,  and  continued  at  intervals  of  ten  or 
fourteen  days  during  the  growing  season,  will  do  much  toward 
checking  the  fungus. 

PEAR  BLIGHT. 

This  disease,  while  not  belonging  to  the  group  of  fungous 
diseases  on  which  we  are  treating,  has  become  so  important  in 
this  State  and  is  doing  such  destructive  work  that  allusion  to 


8  FUNGI   AND    FUNGICIDES. 

it  in  this  connection  is  imperative.  The  pear  blight  is  caused 
by  a  bacterium  discovered  by  Prof.  T.  J.  Burrill,  of  Illinois,, 
and  by  him  named  Bacillus  amylovorus.  Its  point  of  entry 
into  the  tree  is  usually  through  the  blossoms,  although  in  some 
cases  it  may  find  entry  through  wounds  or  abrasions  in  other 
portions.  The  whole  of  the  pomaceous  family,  including 
apples,  medlars,  hawthorns,  and  quinces,  is  subject  to  attack, 
but  the  pear  especially  so,  and  the  tenderer  varieties,  as  the 
Bartlett,  most  of  all.  This  disease  has  received  marked  atten- 
tion from  the  Department  of  Agriculture  at  Washington,  D.  C., 
on  account  of  the  serious  inroads  it  has  made  in  the  pear  sec- 
tions of  the  East,  and  Prof.  M.  B.  Waite  has  made  an  especial 
study  of  it  for  many  years  past.  In  response  to  an  invitation 
from  the  Commission  of  Horticulture  last  fall,  Professor  Waite 
was  detailed  to  study  the  disease  in  California,  and  under  his- 
direction  a  series  of  experiments  has  been  made.  So  far  the 
only  method  of  fighting  this  disease,  and  the  one  which  has 
been  in  vogue  for  many  years  in  the  East,  is  to  cut  out  the 
affected  portions  of  the  tree  well  below  the  point  of  infection. 
An  important  feature  of  this  work  is  the  disinfection  of  the 
tools  used  in  the  cutting-out  process.  Unless  this  is  properly 
done,  the  tools  themselves  may  become  the  medium  of  distribu- 
tion of  the  disease.  Professor  Waite  is  positive  in  his  assertion 
that  if  the  work  of  cutting  out  the  infected  portions  is  con- 
scientiously and  generally  performed,  there  is  little  danger  to- 
be  apprehended  from  this  disease. 

GOOSEBERRY  MILDEW. 

In  some  sections  of  the  State  it  is  almost  impossible  to  raise 
good  gooseberries,  on  account  of  mildew.  This  fungus  appears 
in  the  spring  upon  the  newly  developed  leaves  and  buds,  and 
later  appears  as  a  white  powdery  mass,  caused  by  the  numerous 
^fenuaoer  spores.  Later  in  the*  season  it  attacks  the  young 
berries,  which  are  rendered  unmarketable,  or  in  very  bad  cases 
the  entire  crop  drops  prematurely. 

Spray  with  a  solution  of  potassium  sulphide  when  the  leaves 
commence  unfolding,  and  repeat  in  from  two  to  three  weeks. 

During  the  winter  remove  all  old  canes  and  spray  with  the 
Bordeaux  mixture  (formula  B). 


FUNGI    AND    FUNGICIDES. 


ANTHRACNOSE. 

Affecting  the  Raspberry,  Blackberry,  and  Rose. 

This  fungus  appears  as  small  reddish-purple  spots  upon  the 
canes  and  leaves  in  the  spring  and  early  summer.  These  spots 
are  scattered  over  the  surface  of  the  new  growth  near  the 
ground,  and  have  a  distinct  purplish  margin,  representing  the 


FIG.  7.    Rose  leaf  black  spot. 


FIG.  8.    Strawberry  leaf  blight. 


division  between  the  healthy  and  diseased  tissue.  As  the 
season  advances  these  spots  increase  in  size,  and,  merging  with 
others,  form  irregular,  longitudinal  blotches,  which  in  very 
bad  cases  girdle  the  cane. 

Use  the  Bordeaux  mixture  (diluted  formula)  before  the 
leaves  open,  and  repeat  at  intervals  of  two  weeks,  spraying  the 
canes  which  are  starting  out  of  the  ground. 

Removing  the  old  canes  and  burning  them  will  greatly 
reduce  the  disease. 


10  FUNGI   AND   FUNGICIDES. 

ORANGE  RUST. 

This  disease  is  familiar  to  most  growers  of  blackberries  and 
raspberries.  The  disease  becomes  noticeable  soon  after  the 
leaves  expand  in  the  spring,  turning  them  a  golden  color. 
Soon  small  orange-colored  spores  appear  on  the  surface  of  the 
leaves.  From  these  spores  develop  the  winter  spores,  which 
spread  to  the  growing  shoots  just  starting  from  the  ground  and 
remain  there  until  spring,  to  again  infest  the  plant. 

All  diseased  canes  should  be  cut  and  burned  whenever  dis- 
covered. Spraying  with  the  ammoniacal  copper  carbonate 
solution  will  prove  helpful,  if  applied  on  the  winter  spores. 

ONION    MILDEW. 

California,  with  her  large  seed  gardens,  has  suffered  very 
much  from  onion  mildew  in  abnormal  seasons.  The  seed 
onions  carry  the  hibernating  spores,  which  soon  attack  the  new 
growth  in  spring.  The  disease  is  easily  recognized  by  the 
grayish,  velvety  coating  on  the  new  tops  and  blossom  stalks. 
If  the  land  is  to  be  used  again  for  onions,  all  tops  remaining 
in  the  field  after  the  seed  has  been  collected  should  be  burned, 
and  should  never  be  plowed  under,  as  is  generally  practiced. 
Rotation  of  crops  is  much  the  safer  preventive. 

Wherever  practicable,  the  ammoniacal  copper  carbonate 
solution  can  be  used  to  good  advantage. 

BEAN  ANTHRACNOSE. 

Young  bean  pods  are  often  attacked  by  this  disease,  some 
varieties  more  than  others.  It  can  be  readily  recognized  by 
small  reddish-brown  spots,  slightly  depressed,  on  the  surface 
of  the  pods.  These  spots  increase  in  size  rather  rapidly  and, 
connecting  with  others,  form  long  discolored  blotches.  The 
pod  becomes  stunted  and  the  young  beans  are  generally  shriv- 
eled. Seed  from  diseased  plants  should  never  be  used  for 
planting,  as  the  spores  upon  them  will  first  infest  the  young 
growing  plants  and  from  them  spread  to  the  newly  developed 
pods. 

Soaking  the  seed  in  a  diluted  ammoniacal  copper  carbonate 
solution  before  planting  is  a  sure  preventive.  Spraying  with 
the  Bordeaux  mixture  (diluted  formula)  has  given  good  results. 
Burning  the  old  plants  after  harvest  and  making  a  clean  cul- 
ture in  general  have  much  to  do  with  a  successful  checking  of 
the  fungus. 


FUNGI   AND    FUNGICIDES.  11 

TOMATO  ROT. 

When  the  fruit  of  the  tomato  is  about  half  grown  it  is  sub- 
ject to  the  attack  of  rot.  The  first  appearance  of  this  disease 
is  a  small  blackish-brown  spot,  which  rapidly  increases  in  size. 
The  underlying  tissues  of  the  fruit  are  destroyed  by  the  fun- 
gous threads,  and  the  side  of  the  fruit  affected  becomes  flattened. 

Wherever  this  disease  appears  it  can  be  checked  to  a  certain 
degree  by  thinning  out  the  plants  and  allowing  more  sunshine 
to  reach  the  fruit. 

Spraying  with  the  Bordeaux  mixture  (formula  B)  when  the 
fruit  is  first  forming  will  often  check  the  fungus. 

POTATO  BLIGHT  OR  ROT. 

This  disease  attacks  the  leaves,  stems,  and  tubers.  It  is  first 
noticed  upon  the  leaves  by  the  sudden  appearance  of  brownish 
or  blackish  areas,  which  soon  become  soft  and  foul-smelling. 
This  disease  generally  occurs  in  our  coast  counties  and  other 
sections  where  plenty  of  moisture  exists.  The  presence  of  a 
few  successive  hot,  dry  days  in  these  districts  checks  its  rapid 
development. 

Spraying  with  the  Bordeaux  mixture  (formula  B)  when  the 
growth  just  appears  above  ground,  especially  in  sections  where 
this  fungus  is  known  to  exist,  is  very  important.  Affected 
potatoes  should  never  be  used  for  seed,  and  all  vines  remain- 
ing after  harvest  should  be  burned. 

POTATO  SCAB. 

This  is  a  very  widespread  disease,  and  is  readily  recognized 
by  the  dark,  rough  surface  which  occurs  in  spots  all  over  the 
tubers. 

This  disease  can  be  successfully  controlled  by  treating  the 
seed  potatoes  in  a  solution  of  corrosive  sublimate.  Immerse 
them  for  a  couple  of  hours  in  the  liquid,  and  after  their  re- 
moval allow  them  to  dry  before  cutting  them  for  planting. 
All  potatoes  thus  treated,  if  not  planted,  must  be  destroyed,  as 
there  is  sufficient  poison  on  them  to  make  them  dangerous  to 
use  as  food  or  to  feed  to  stock. 


12  FUNGI   AND    FUNGICIDES. 

ROOT  KNOT. 

No  fungous  disease  is  easier  recognized  than  this.  The  very 
prominent  black  or  brown  wart-like  excrescences  upon  the 
trunk  and  roots,  below  ground,  of  all  stone-fruit  trees,  readily 
reveal  its  presence. 

Cut  away  the  knot  in  the  fall  or  winter  and  allow  the  wound 
to  dry,  then  with  a  swab  apply  a  saturated  solution  of  blue- 
stone  to  the  affected  part.*  This  may  be  repeated  two  or  more 
times  as  long  as  the  trees  remain  dormant.  Never  apply  it  to 
the  tree  when  the  sap  is  flowing.  After  the  knots  have  been 
treated  the  soil  is  thrown  back  again,  covering  the  exposed 
roots.  The  Bordeaux  mixture  (formula  A),  applied  in  a  sim- 
ilar way,  has  also  given  good  results.  Instead  of  removing  very 
large  knots  it  is  better  to  bore  an  inch  hole  to  the  center  of  the 
knot  and  fill  this  with  either  of  the  above  solutions,  which  will 
permeate  the  tissues  of  the  knot  and  cause  it  to  drop  off  after 
a  few  months. 

OLIVE  KNOT. 

One  of  the  most  serious  diseases  of  the  olive  tree,  in  a  few 
counties  of  California,  is  the  olive  knot,  or  tuberculosis  of  the 
olive,  as  it  is  sometimes  called,  which,  like  the  pear  blight,  is 
a  bacterial  and  not  a  fungous  disease.  The  tubercles,  or  knots, 
which  give  this  disease  its  name,  are  found  singly  and  in  rows 
on  branches  of  all  ages.  The  bacteria  which  cause  the  disease 
form  a  colony  in  the  tissue  of  the  sap-wood,  which  appears 
like  a  small,  transparent  spot.  This  spot,  when  seen  under  a 
high-power  microscope,  is  found  to  consist  of  many  bacteria. 
From  this  spot  soon  develop,  through  different  stages,  the 
tubercle  knots.  On  the  trunks  and  larger  branches  the  knots 
generally  attain  a  large  size. 

The  diseased  parts  of  affected  trees  should  be  carefully  re- 
moved and  immediately  burned.  All  wounds  made  by  the 
removal  of  the  disease  should  be  dressed  with  an  antiseptic 
paint. 

Cuttings  from  diseased  trees  should  never  be  used  for  prop- 
agating purposes. 


*A  saturated  solution  of  bluestone  is  all  that  water  will  dissolve.  But  it 
is  advisable  to  leave  some  undissolved  bluestone  in  the  bottom  of  the  vessel, 
as  this  will  indicate  that  the  water  has  taken  up  all  the  bluestone  it  can. 


FIG.  9.    Olive  knot. 


14 


FUNGI    AND    FUNGICIDES. 


POWDERY  MILDEW  OF  THE  ROSE. 

This  disease  is  too  well  known  to  the  lovers  of  tea  roses  to 
need  much  description.  It  is  the  white  powdery  fungus  which 
is  so  often  seen  on  the  new  growth,  leaves,  and  buds  of  the 
rose  bush,  marring  the  beauty  and  blasting  the  buds  of  many 
of  our  choicest  varieties. 

If  taken  in  hand  when  it  first  makes  its  appearance  on  the  new 
growth,  dusting  with  sublimed  sulphur  will  check  its  spread. 
Spraying  with  the  Bordeaux  mixture  (diluted  formula),  just 
before  the  new  growth  starts,  will  prevent  its  appearance. 


FIG.  10.    Rose  rust. 
ROSE  RUST. 

This  disease  confines  itself  to  the  hybrid  perpetual  roses, 
and  is  easily  recognized  by  the  orange-colored  spots  on  the 
under  side  of  the  leaves,  which  in  very  bad  cases  become 
entirely  covered. 

After  pruning  rose  bushes  in  the  fall,  they  should  be  thor- 
oughly sprayed  with  the  Bordeaux  mixture  (formula  B).  All 
leaves  should  be  gathered  and  burned,  as  these  contain  the 
winter  spores.  If  the  fungus  was  very  severe  during  the 
season,  spraying  again  in  the  spring,  just  when  the  growth 
starts,  with  the  ammoniacal  copper  carbonate  solution  or  the 
Eau  Celeste  solution,  will  greatly  aid  in  checking  the  trouble. 


FUNGI   AND   FUNGICIDES.  15 


FORMULAS. 


LIME,  SULPHUR  AND  SALT. 

Unslaked  lime 40  pounds. 

Sulphur 20  pounds. 

Salt i 15  pounds. 

Water 60  gallons. ' 

Place  10  pounds  of  lime  and  20  pounds  of  sulphur  in  a  boiler 
with  20  gallons  of  water,  and  boil  over  a  brisk  fire  for  not  less 
than  one  hour  and  a  half,  or  until  the  sulphur  is  thoroughly 
dissolved.  When  this  takes  place,  the  mixture  will  be  of  an 
amber  color.  Next  place  in  a  cask  30  pounds  of  unslaked  lime, 
pouring  over  it  enough  hot  water  to  thoroughly  slake  it;  and 
while  it  is  boiling,  add  the  15  pounds  of  salt.  When  this  is 
dissolved,  add  to  the  lime  and  sulphur  in  the  boiler,  and  cook 
for  half  an  hour  longer,  when  the  necessary  amount  of  water 
to  make  the  60  gallons  should  be  added. 

A  much  easier  method  of  preparing  the  above  wash  is  as 
follows:  Make  the  sulphur  into  a  thin  paste  with  hot  water; 
place  the  unslaked  lime  in  a  tight  barrel  and  add  the  sulphur 
paste  and  from  10  to  15  gallons  of  boiling  water.  Cover  the 
barrel  with  sacks  and  a  wooden  cover  and  let  it  stand.  After 
the  violent  boiling  has  subsided,  the  mixture  must  be  stirred 
thoroughly  until  all  indications  of  boiling  stop.  Then  add  the 
salt  and  enough  hot  water  to  be  able  to  strain  the  mixture  into 
the  spray  tanks,  and  add  the  required  quantity  of  boiling 

water. 

BORDEAUX  MIXTURE. 

Formula  A. 

Copper  sulphate  (bluestone) ._    8  pounds. 

Quicklime 10  pounds. 

Water 1 50  gallons. 

Formula  B. 

Copper  sulphate  (bluestone) 5  pounds. 

Quicklime .._ 6  pounds. 

Water 50  gallons. 

Diluted  Formula. 

Copper  sulphate  (bluestone) 2  pounds. 

Quicklime 2  pounds. 

Water 30  gallons. 

Dissolve  the  copper  sulphate  in  a  barrel  containing  10  to  12 
gallons  of  water.  Slake  the  quicklime  and  thin  it  to  a  creamy 


16  FUNGI   AND    FUNGICIDES. 

whitewash.  Pour  the  whitewash  very  slowly  through  a  wire 
screen  into  the  copper  solution.  Stir  the  mixture  thoroughly, 
and  add  enough  water  to  make  50  gallons  in  all.  Stir  occa- 
sionally while  applying  as  a  spray  to  the  trees. 

In  the  preparation  of  the  Bordeaux  mixture  it  is  necessary 
that  the  ingredients  should  be  mixed  in  a  wooden  vessel.  If 
an  iron  one  is  used  the  copper  will  go  to  the  iron  and  the  effect 
of  the  spray  be  largely  neutralized. 

Apply  the  wash  cold  and  as  soon  as  possible  after  it  is 
prepared.  Never  allow  it  to  stand  over  night. 

AMMONIACAL  COPPER  CARBONATE  SOLUTION. 

Copper  carbonate  .  _'. ...    6  ounces. 

Ammonia . 3  pints. 

Water 50  gallons. 

Dissolve  the  copper  carbonate  in  the  ammonia  and  add  the 
water. 

Caution:  Use  np  more  ammonia  than  is  required  to  dis- 
solve the  copper  carbonate.  Ammonia  is  variable  in  strength, 
and  the  amount  required  must  be  tested  in  practice. 

POTASSIUM  SULPHIDE  SOLUTION. 

Potassium  sulphide 1  ounce. 

Hot  water 2  gallons. 

Dissolve  the  potassium  in  hot  water,  and  use  as  a  spray 
when  cold. 

EAU  CELESTE  SOLUTION. 

Copper  sulphate 2  pounds. 

Ammonia 1  quart. 

Water. ._ .'.  50  gallons. 

Dissolve  the  copper  sulphate  in  6  gallons  of  water,  using  a 
wooden  vessel,  then  add  one  quart  of  ammonia  and  sufficient 
water  to  make  50  gallons  of  wash. 

CORROSIVE  SUBLIMATE  SOLUTION. 

Corrosive  sublimate 2^  ounces. 

Hot  water 2    gallons. 

Dissolve  the  corrosive  sublimate  in  the  water,  let  it  stand 
for  about  10  hours,  and  then  add  sufficient  water  to  make  15 
gallons  of  spray. 


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